Groundwater is a key resource in the Middle East and Northern Africa region for both water supply and agriculture. While farmers in irrigated areas have tapped aquifers as a response to dwindling and uncertain surface water supply, investors have drilled wells and expanded agriculture into arid or desert areas. Most countries in the region have adopted standard water regulations, with emphasis on zoning (of stressed areas), licensing, metering and sometimes pricing, but enforcement has been problematic, and results on the ground modest to non-existent. This reflects a lack of material and financial means to handle tens and sometimes hundreds of thousands of dispersed wells but also a lack of political will. This can be explained by the state’s lack of appetite for curtailing access to a resource that substantially contributes to the rural economy, a drop in state authority after the Arab Spring, inter-sectoral policy contradictions, the interest of politically well-connected investors, and sometimes the complexity of tribal politics. While state-centred governance has been largely ineffective, attempts at co-management or instilling a degree of participation from users have also been limited and unconvincing, reflecting wider governance systems in the region. The worrying depletion of many vital aquifers in the region is increasing the cost of abstraction, heightening social differentiation as smaller farmers are pumped out, and foreshadows a gradual collapse of the groundwater economy.